<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>小球落地</title>
    <script>
      let height = 100,
        total = 100
      for (let i = 0; i < 10; i++) {
        height /= 2
        total += height * 2
      }
      alert(`共经过${total}米, 第10次反弹高度为: ${height}米.`)
    </script>
  </head>
  <body></body>
</html>
